Sold on Language, by Julie Sedivy & Greg Carlson (Wiley-Blackwell, £16.99)What's the difference between "a curiously strong mint" and "the curiously strong mint"? In an advert, the definite article plants the idea that everyone is already talking about a particular mint, the identity of which has now been revealed. Cunning. Billed as an inquiry into the language of advertising, this book is more a compilation of ideas in linguistics and explanations of "priming" strategies or cognitive biases, illustrated by ads through the decades, from super-classy Rolls-Royce print ads to smug-hipster "I'm a Mac" TV spots.

The academic authors strain too hard at times for a down-with-the-kids informality ("It would be fun to put Calvin Coolidge in a time machine." Would it really?), but they tell a good story, from the musings on propaganda of Freud's nephew, Edward Bernays, through philosopher Paul Grice on implication, to Barack Obama being named Marketer of the Year in 2008 by Advertising Age. They also dispense copywriting advice: "You might, for instance, suggest that they use your product to 'maintain a smooth complexion' rather than improve their currently crappy one." I don't know: the latter option has a certain attractive edginess.

The Offensive Internet, edited by by Saul Levmore & Martha C Nussbaum (Harvard, £20.95)Advertising is considered, on some readings of US law, to be "low-value speech": an interesting concept that lumps advertising in with bribery, threats and other communication not worthy of robust First Amendment protection. This essay collection is itself weirdly misadvertised by its dumb title (how can "the internet" or even a part of it be generally "offensive"?): it is really about online privacy violation and harassment. There are some egregious examples: of student forums where men scrawl violent enraged fantasies about named women on the same campus, and other campaigns of concerted defamation.

In the light of such harms (which go far beyond "offence"), most of the contributors agree that speech on the internet is under-regulated. Among the most incisive essays, Brian Leiter's excellent piece on "cyber-cesspools" suggests persuasively that victims of malicious reputation damage ought to be able to appeal to a "Google panel" to have those search results deleted. Frank Pasquale proposes letting subjects "annotate" public information about them; and Levmore foresees an inevitable restriction of anonymity or pseudonymity. Nussbaum's very striking contribution, meanwhile, diagnoses a more general social problem: "a diseased norm of masculinity" that drives (some) men to try to humiliate women online. All too plausible.

Who Sings the Nation-State?, by Judith Butler & Gayatri Chakravorty Spivak (Seagull, £14)Butler, favourite offender against a certain dull-headed British clique's pseudo-idea of intellectual clarity, here plays tag with the critic Spivak in a sparklingly wide-ranging and suggestive conversation. Butler begins by separating the compound "nation-state" and considering what either means to a refugee.

Spivak, for her part, proposes a "critical regionalism" in response to both nationalism and globalisation. She is enjoyably sardonic, redescribing "development" as "sustainable exploitation", and makes pointed comments about the rhetorical deployment of "Confucianism" or "a monolithic idea of Palestine". Both thinkers address Hannah Arendt's question of how people with different origins or cultural practices may live together. It's a relief to read their humanely nuanced exploration, not long after David Cameron exposed to the public his tough-love muscle on "multiculturalism".